Tire building drum

ABSTRACT

A TIRE BUILDING MACHINE COMPRISING AN EXPANSIBLE DRUM ON WHICH TIRES ARE BUILT. THE DRUM INCLUDES A PAIR OF SETS OF SEGMENTS MOVABLE RADIALLY OF THE DRUM AXIS AND WHICH ARE COVERED WITH A RUBBER SLEEVE AND ARE DISPOSED BETWEEN TWO SETS OF FINGERS WHICH ARE ALSO MOVABLE RADIALLY OF THE DRUM AXIS. THE FINGERS ARE DESIGNED TO HOLD A PAIR OF WIRE BEADS CONCENTRICALLY OF THE LONGITUDINAL AXIS OF THE BUILDING DRUM IN EQUIDISTANT SPEED RELATION FROM THE CENTERPLANE OF THE DRUM. THE SEGEMENTS ARE MOVABLE RADIALLY OUTWARDLY OF THE DRUM TO FORM SHOULDERS IN THE CARCASS PILES ON WHICH THE BEADS MAY BE SEATED, AFTER WHICH THE TURN-UP OF THE PILES AND TIE-IN OF THE WIRE BEADS ARE MADE, AND TREAD AND SIDEWALL ARE APPLIED TO COMPLETE THE UNCURED TIRE. THE FINGERS AND SEGMENTS HAVE RIGID MATERIAL ENGAGING SURFACES. THE CENTER SECTION OF THE   BUILDING DRUM INTERMEDIATE THE SEGMENTS HAS A SUBSTANTIALLY RIGID MATERIAL SUPPORTING SURFACE AND, TOGETHER WITH THE SEGMENTS, PROVIDES A FIRM WORING SURFACE FOR BUILDING THE TIRE.

Oct. 17, 1972 g. s. wooDHALL ErAL 3,698,987

TIRE BUILDING DRUM 5 Sheets-Sheet l Filed Dec. 18, 1970 |NvENToRs EDWINS. WOODHALI. PAUL E. APPLEBY JOHN W TOUCHETTE Oct. 17, 1972 E. s.wooDHALL ETAL 3,698,987

TIRE BUILDING DRUM 5 Sheets-Sheet 2 Filed Deo. 18, 1970 INVENTORS EDWINS. WOODHLL -PAUL A'PPLEBY W. TOUCHETTE JOHN Oct. 17, 1972 Filed Dec. 18,1970 E. s. WOQDHALL ETAL 3,698,987

TIRE BUILDING DRUM 5 Sheets-Sheet 5 EDW//V S. WOOD/'LL PAU/ E. APPLEBYJOHN W. TOUCHETTE Oct. 17, 1972 E. sA WOODHALL EVAL 3,698,987

TIRE BUILDING DRUM 5 Sheets-Sheet 4 Filed Dec. 18, 1970 INVENTORS 9EDW//V S. WUODHALL PAUL E. APPLEBY JOHN W TOUCHETTE CCL-17, 1972 E. s,WOODHALL EVAL 3,698,987

' TIRE BUILDING DRUM Filed Dec. 18, 1970 5 Sheets-Sheet 5 96 80 8 'I 96I 95 Il A v. v

INVENTORS Eow//v s. woop/mu PAU/ E. APPLEr .10H/v nl. rol/CHUTE nitedStates Patent yll 3,698,987 TIRE BUILDING DRUM Edwin S. Woodhall andPaul F. Appleby, Cuyahoga Falls, and John W. Touchette, North Canton,Ohio,

assignors to The Goodyear Tire & Rubber Company,

Akron, Ohio Filed Dec. 18, 1970, Ser. No. 99,428 Int. Cl. B29h 17/22U.S. Cl. 156-401 43 Claims ABSTRACT OF THE DISCLOSURE A tire buildingmachine comprising an expansible drum on which tires are built. The drumincludes a pair of sets of segments movable radially of the drum axisand which are covered with a rubber sleeve and are disposed between twosets of fingers which are also movable radially of the drum axis. Thelingers are designed to hold a pair of wire beads concentrically of thelongitudinal axis of the building drum in equidistant spaced relationfrom the centerplane of the drum. 'I'he segments are movable radiallyoutwardly of the drum to form shoulders in the carcass plies on whichthe beads may be seated, after which the turn-up of 'the plies andtie-in of the wire beads are made, and tread and sidewall are applied tocomplete the uncured tire. The fingers and segments have rigid materialengaging surfaces. The Center section of the building drum intermediatethe segments has a substantially rigid material supporting surface and,together with the segments, provides a firm working surface for buildingthe tire.

The foregoing abstract is not to be taken as limiting the invention ofthis application, and in order to understand the full nature and extentof the technical disclosure of this application, reference must be madeto the accompanying drawings and the following detailed description.

This invention relates to tire building machines and more particularlyto a novel and improved tire building machine for building radial-beltedtires.

It is the primary object of the present invention to provide a tirebuilding machine which will provide increased accuracy in the locationof the components of the tire, particularly the beads, during thebuilding process.

It is further an object of the invention to provide such a tire buildingmachine which is capable of being readily modified to vary the sizes anddiameter of tire which may be built on the machine.

It is still further an object of this invention to provide a tirebuilding machine having a novel and improved drum which is expandablebetween two cylindrical congurations of different diameters and which iscapable of shaping a tire carcass to toroidal shape While at the sametime providing a substantially rigid building surface in bothcylindrical configurations thereof.

Other objects will be in part obvious, and in part pointed out more indetail hereinafter.

The invention accordingly comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereafter set forth and the scope of theapplication of which will be indicated in the appended claims.

In the drawings:

FIG. 1-1A is a longitudinal, partially offset cross-sectional view,taken substantially along fthe lines 1-1 of LFIG. 2, of a buildingmachine constructed in accordance with the invention;

FIG. 2 is a section of the drum of FIG. l viewed substantially from theline 2-2 of FIG. 1;

FIG. 3 is a partial section of the drum of lthe machine 3,698,987Patented Oct. 17, 1972 ice of FIGS. l and 2 as modified to decrease thelength thereof and increase the diameter thereof;

FIG. 4 is a partial section of the drum of FIG. 3 as modified to furtherincrease the diameter thereof;

FIG. 5 is another partial section of the drum of FIG. 4, the fingers andsegments being shown in their fully retracted positions relative to thelongitudinal axis of the drum;

FIGS. `6A-6I are a series of schematic diagrams showing the sequentialoperation of the building machine; and

FIG. 7 is a fragmentary plan view of a portion of the drum of themachine of FIGS. l-lA.

Referring -generally to the drawings, and more particularly to FIGS.1-1A, there is shown a building machine comprising a drum 10 which inturn comprises an elongated hollow shaft 11 having an axial bore 12. Adrive screw 13 with a pair of oppositely threaded portions 14 and 15, iscentrally disposed within the bore 12 of the shaft 11. The drive screw13 is journalled in a pair of bearings 16 and 17 disposed at adjacentinboard and outboard ends 18 and 19, respectively, of the drum shaft 11,for rotation about the longitudinal axis of the building drum 10", whichcoincides with the longitudinal axes of the drum shaft 11 and drivescrew 13. A washed and nut assembly 20i is mounted on the outboard end21 of the drive screw 13 for preventing axial movement of the drivescrew 13 in the bore 12.

The inboard end 24 of the drive screw 13 protrudes from the buildingdrum 10k for coupling engagement with a drive shaft 24 for rotating thedrive screw 13 to axially expand and contract the drum. The shaft 24' iscantilever supported on the main housing or head stock 9' of the tirebuilding machine of which the drum 10 is a part. A drive shaft 8disposed coaxially about the drive shaft 24' also extends in cantileverfashion from the head stock 9 and is fixed to a flange at one end of thedrum shaft 11 to support the drum and to rotatably drive the same.

A pair of nuts 28 and 29 are threadably mounted on the threaded portions14 and 15 of the drive screw 13 for movement along the longitudinal axisof the building drum 10 in response to rotation of the drive screw 13. Apair of annular hubs 30 and 31 are slidably mounted on the drum shaft 11for movement coaxially thereof and are keyed by sets of similar pins 32to the nuts 28 and 29. The pins 32 extend through and are slidable inslots 33 in the shaft 11 which extend parallel to the rotational axis ofthe shaft. The pins thus prevent rotation of the hubs 30 and 31 and nuts28, 29' about the shaft 11. The hubs 30 and 31 are equally spaced fromvthe centerplane OP of the drum 10. The centerplane of the drum is aplane disposed midway between the ends of the drum and extending atright angles to the rotational or longitudinal axis of the drum. Withreference to FIG. l-A, the hubs 30 and 31 each comprises an innercylindrical portion 34a slidably mounted on the shaft 11 and an annularflange 34b extending radially of the inner portion 34a from a pointintermediate the ends thereof. The radially outer end of the flange 34bterminates in an outer second cylindrical portion 34e extending axiallyinwardly of the drum. in radially spaced relation to the inner portion34a to form an annular chamber 34 disposed concentrically of the drumaxis.

An annular piston 35 is slidably mounted in the chamber or cylinder 34.Mounted for movement with each piston is a cam 36 comprising, as shownin FIG. 1, a cylindrical surface 37 extending from the piston 35 andcoaxially inwardly of the drum. The Isurface 37 terminates at its innerend in one end of a conical surface or ramp 38 extending coaxially ofthe surface 37 and terminating at its other smaller diameter end in arelatively short cylindrical surface 39 also coaxial with the surface37. The inner end of the surface 39 terminates in a conical surface 36aextending coaxially of the shaft 11. The surface 36a extends from thesurface 39 toward the shaft 11 and is a part of a generally conicalportion of the cam 36, the inner smallei diameter end portion of whichis slidably engaged coaxially over the shaft 11.

The drum further comprises a pair of segment assemblies 42 and 43 eachdisposed in concentric relation around the longitudinal axis of thebuilding drum 10, and each equally spaced in parallel relation from thecenterplane CP of the building drum 10. The segment assemblies 42 and 43each comprises a housing 44 which is fixed to one of the hubs 30, 31. Aplurality of bores 45 are provided in each of the housings 44 inequi-angularly spaced relation about the longitudinal axis of the drum.The bores 45 extend radially of the axis of the drum and are incommunication with the annular ybores 34 of the hubs 30, 31.

A lifter member or rod 46 is slidably received in each of the bores 45for movement radially of the drum. Each lifter rod 46 carries at itsinner end a roller 47 for rolling engagement with the ramp 36a of thecam 36 when the associated piston 35 moves in an axial direction towardsthe centerplane of the drum. As illustrated in FIG. 4, the rollers 47 ofthe lifter rods 46 rest on the cylindrical surfaces 39 of the cams 36,when the lifter rods 46 are in their fully extended or radiallyoutermost position relative to the longitudinal axis of the drum.

With further reference to FIGS. l-lA, a segment 48 is mounted on theouter end of each lifter member 46, Each segment has at its radiallyoutermost extremity a generally parti-cylindrical rigid surface 50 forsupporting rubberized plies of carcass material. 'Ihe parti-cylindricalsurfaces 50 are disposed with their axes parallel to the axis of thedrum, and in this instance the term parallel is intended to include thecase where the axes of the particylindrical surfaces 50 are coincidentwith the rotational axis of the drum.

The parti-cylindrical surfaces 50 of each set 42 and 43 of segmentscooperate to provide a generally cylindrical surface in both theradially inner and outermost positions of the segments. Each segment 48is provided with an arcuate groove 51 extending about the rotationalaxis of the drum which with the grooves of the remaining segments ineach set delines a generally annular groove generally concentric withthe drum axis for receiving a spring such as an elastomer O-ring 52 forbiasing the segments 48 and lifter rods 46 radially inwardly of thelongitudinal axis of the building drum. Thus, when the cams 36 are movedout of wedging relationship with the rollers 47 of the lifter rods 46,the rubber O-rings 52 act to return the segments 48 from their fullyextended position to their rest positions closer to the longitudinalaxis of the building drum 10, where the rollers 47 are engaged with thesurface 53 of the annular cylinders 34.

A generally cylindrical sleeve 55, composed of any suitable elastomericmaterial, e.g., rubber, is disposed coaxially of the drum. The sleeve isdisposed over the segments 48 and is secured at its ends to the housings44 by a pair of annular clamping rings 56 and 57, which are fastened tothe housings 44. The clamping rings 56 and 57, each have a plurality ofslots 58, which extend radially of the longitudinal axis of the drum.The slots 58 in each clamping ring 56, 57, preferably, correspond innumber to that of the bores 45 formed in the respectively associatedhousings 44.

With reference to FIGS. l-lA, a bead gripping member of linger 59 isslidably mounted in each of the slots 58 of the clamping rings 56 and57, for movement radially of the drum axis. For a reason to behereinafter explained, the lingers 59 are offset about the drum axisrelative to the next adjacent segment 48. The two sets of fingers 59 areequally spaced from the centerplane of the drum 10 a distance greaterthan are the segment assemblies 42 and 43. Each finger 59 is providedwith a slot 60 extending at right angles to the next adjacent slots 5,8

in the next adjacent clamping ring, and the bases 0f the slots 58 are insliding engagement. The outer end of each slot 60 forms a stop 63 forengaging the outer perlphly of the next adjacent clamping ring 56 tolimit movement of the linger 59 in a radial direction towards thelongitudinal axis of building drum 10;

With reference to FIG. 1, each linger 59 is provided with an arcuategroove 64 extending about the drum axis, with the grooves 64 of theother lingers in each set thereof forming a circular groove forreceiving a spring, such as an O-ring 65 composed of any suitableelastomeric material, c g., rubber. The O-ring 65 acts to bias thelingers 59 in a direction towards the longitudinal axis of building drum10.

A plurality of levers or links 68 are each associated with, andpivotally mounted at one end on, one of a pair of mounting rings 70secured between a flange on the hubs 30, 31 and the adjacent housings 44of the segment assemblies 42 and 43. Each lever 68 is operativelyassociated with one of the lingers 59. A roller 71 is mounted on thefree end 72 of each lever 68 for rolling engagement along the cam 36 andonto the land 37 thereof. A second roller 73 is mounted intermediate theends of each lever 68 and is engageable with the radially inner end ofthe respectively associated finger 59 to move the linger in a directionradially outwardly of the longitudinal axis of the building drum as theother roller 71 of the lever 68 is moved radially outwardly of the drumby the respectively associated cam 36. Each linger 5,9 has at itsradially outermost extremity a rigid parti-cylindrical material engagingsurface 74, the axis of which extends parallel to the longitudinal axisof the building drum 10. In other words, no portion af linger 59 extendsradially outwardly beyond the surface 74. It is intended to includewithin the use of the term parallel as applied to the axis of a surface74 the situation wherein the axis is coincident with the drum axis. Inthe at rest position of the lingers 59, the surfaces 74 are spaced fromthe drum axis a distance not substantially greater than the surfaces 50of the segments 48.

An arcuate groove 75, extending about the drum axis is provided in eachlinger 59 in radially inwardly spaced relation and in registry with thematerial engaging surface 74 with the groove facing axially outwardly ofthe drum. The clamping rings 56 and 57 each carry a projecting annularlug 76 for registry in an annular groove 77 formed in an adjacentturn-up bladder assembly 78 located at an outboard end of the drum. Eachbladder assembly comprises an auxiliary drum 79, which is disposedcoaxially of the building drum. 10l and an annular extensible turn-upbladder 80 which is composed of a suitable elastomeric material, e.g.,rubber. Each turn-up bladder 80 has an annular end or nose portion 81projecting into the arcuate grooves 75 formed in the next adjacent setof fingers 59. The turn-up bladders 180 in their deflated condition havean outer diameter substantially the same as that of the rubber sleeve 55disposed over the segments 48. IEach bladder 80 is anchored relative toits auxiliary drum 79 at a location closely adjacent to but spacedaxially outwardly from the axially inboard end of the bladder thusforming the nose portion 481.

A plurality, e.g., twelve, of similar center segments or cover plates 84are equi-angularly spaced around the longitudinal axis of the buildingdrum lill, intermediate the segment assemblies 42 and 43. The coverplates 84 correspond in number to the segments 48 and lingers 59 andeach consists of a parti-cylindrical member, the axis of which extendsparallel to the longitudinal axis of the drum, and by parallel we meanto include coincidence with the drum axis. The cover plates 84 each haveopposite ends 85 and 86, which are radially outwardly disposed inoverlapped relation with respect to the adjacent segment 48. Anoperating piston 88, is associated with each cover plate 84 for movingthe cover plate radially outwardly of the drum simultaneously with therespectively associated segments 48. The cover plates 84 provide supportfor the carcass plies between the segments 48, and together with thesegments 48 provide a iirm working surface on which the tire is built.The pistons 88 are respectively slidably engaged in a plurality of boresor cylinders extending radially inwardly of and from the outer peripheryof an annular member 87 disposed coaxially over the shaft 11. The coverplates 84 being in overlapped relation with the segments 48, do nothinder movement of the segments 48 when the drive screw 113 is operatedto move the hubs 30 and 31 toward and away from the centerplane of thebuilding drum 10. The cover plates 84 preferably are sufliciently thinthat the diameter of the center portion of the drum is not substantiallygreater than that of the end portions and yet sufliciently thick thatthe center portion provides a iirm working surface for building thetire.

The overall diameter D of the segments 48 in their rest positions, asshown in FIG. 1A, is sufficient to build a tire carcass with a 13 inchtire bead suitable for mounting on a conventional 13 inch rim. Thediameter of the tire drum may be increased by mounting extensions orblocks on the segments. For example, blocks 89 (FIG. 3) and 90 (FIGS. 4and 5), variable in thickness by one-half inch, are removably mounted onthe segments 48 to increase the building diameter of the tire drum 101for building tires with 14 and 15 inch tire bead suitable for mountingon corresponding size conventional rims. As will be seen from acomparison of the segments 48 and 48', the segments are provided indifferent lengths to provide for different size tires of the same beaddiameter. vDifferent fingers 59', 59", greater in overall length, asmeasured radially of the drum, by increments of one-half inch, are alsoused in corresponding relation to the size block and building diameterrequired. Moreover, correspondingly dimensioned adapter rings 91 and 92'are used to seat and hold the ends of a larger rubber sleeve 55', 55",which is clamped in position by clamping rings 56 and 57', which arealso in corresponding relation to the size of the adapter rings 91' and92' and extension blocks 89 and 90.

As shown in FIG. 2 air passages 102, 103, .10'4 and 105 are provided inthe shaft -11 and extend longitudinally thereof. For the purpose ofillustration, two of these passages 102 and 104 are shown in FIGS. 1-1Arotated from their actual position as shown in FIG. 2 into the plane ofFIGS. 1-1A. The passages extend outwardly of the end of the shaft `-11which is supported by the head stock 9 for connection to suitablesources of pressurized air. The passage 104 extends substantially thefull length of shaft 11. A pair of air hoses 94 are connected at one endto the passage 104 adjacent its ends, and at their other ends to thehubs 30 and 31 for supplying air to actuate the pistons 35 for electingmovement of the segments 48 and fingers 59. The annular member 87housing the pistons 88 of the cover plates 84 is provided on its innerperiphery with an annular groove 108 which communicates with the passage104 and provides a manifold for the supply of air to actuate the pistons88. A plurality of radially extending passages 106 in the member 87provide communication between the manifold 108 and the pistons 88. Thepassage 105 extends substantially the full length of the shaft 11 as inthe case of the passage 104, and is connected adjacent its opposite endsby hoses 9'3 to the bladders y80. The passage 102, as illustrated inFIG. 1, and in like manner the passage 103, terminates at its inner endadjacent the annular member 87 housing the pistons 818. Morespecifically, the inner end of each passage 102, 103 extends slightlybeyond the annular member 87 and opens outwardly of the shaft 111 onboth sides of the annular member 87. Accordingly, air pressureintroduced through the passages 102, 103 will effect expansion of thesleeve 55. A blocking plate 107 serves to seal the manifold 108 in theannular member 87 from the passage 102, it being understood that thereis a similar arrangement with respect to the passages 103, 105 in orderto isolate the manifold therefrom.

'Referring more particularly to FIGS. 6A-6I, there is shown apredetermined number of plies of tire fabric formed into a cylinder bydisposing the ply or plies about the building drum 10 with the ends ofthe ply or plies extending beyond the ends of the drum. As shown in FIG.6B, wire beads 96 are then located concentrically and axially inwardlyof the ends of the carcass in radially outwardly spaced relation to thecarcass and in predetemined equally spaced relation from the centerplaneof the building drum 10. Pressurized air is then introduced into thepassage 104 to actuate the annular pistons 35 to move the cams 36longitudinally of the drum and effect movement of the fingers 59simultaneously radially outwardly of the drum to clampingly engage thecarcass plies 95 against the inner periphery of the wire beads 96 asshown in FIG. 6C. even though pressurized fluid in the passage 104serves to actuate the pistons 88 of the cover plates 84, the initialintroduction of pressurized fluid into the passage 104 will not resultin movement ofthe pistons 88 as these pistons do not provide sufficientpower to move the cover plates against the action of the elastomericsleeve 55. The fingers 59 concentrically position the wire beads 96relative to the building drum 10. The levers 68 for operating theiingers 59, are in locked position on the land 37, as the pistons 35move further out of the bores 34 to effect expansion of the liftermembers 46 and correspondingly move the segments 48 in a radialdirection away from the longitudinal axis of the building drum 10. Asthe segments 48 expand the sleeve S5, the piston 88 is then permitted tomove the cover plates outwardly of the drum to support the center of thesleeve SS. Simultaneously, the mechanism for rotating the drive screw 13is operated to move the hubs 30 and 31 together in predetermined closerspaced relation to the centerplane CP of the building drum 10 (FIG. 6D).Accordingly, and while the tire fabric remains clampingly engaged withthe inner periphery of the bead, the portion of the tire fabric disposedbetween the beads is radially expanded and axially contracted so as toprovide that portion of the fabric with a pair of annular shouldersextending radially of the drum and in engagement with the sides of thebeads facing axially inwardly of the drum. The shoulders 97 formed inthe tire fabric terminate at their outer ends at a diameter greater thanthe outer diameter of the beads 96 and in a generally cylindricalportion of greater diameter than that at which the tire fabric wasinitially laid about the drum. In order to assure that the shoulders 97are tightly engaged with the sides of the beads, each bead 96 isinitially located axially outwardly of the drum 10 a distance d which isno greater than, and preferably is slightly less than, the thickness tof the tire building material disposed between the bead and the drum. Asa result when the material is expanded radially during radial expansionof the ends of the drum the material forming the shoulder 97 will betightly engaged with the inwardly facing sides of the beads and wherethe distance d is less than the thickness t of the material, the beadswill be moved slightly axially outwardly of the drum during formation ofthe shoulders 97.

During expansion of the drum for the irst diameter of FIG. 6A to thesecond larger diameter of FIG. 6D, the previously mentioned angularoffsetting of the segments 48 and lingers 59 about the drum axis assuresthat there will be no loose cords in the plies when biulding radial plytires which the cords of the plies extend essentially parallel to thedrum axis. More particularly, the space between each next adjacent pairof bead gripping iingers 59 is, in both diameters of the drum, wholly inregistry with the surface 50 of a next adjacent segment 48. Thus, evenin the second larger diameter of the drum the spaces between nextadjacent vfinger 59 and segments 48 do not provide a continuous grooveover the full length of the drum and into which cords may droop when thedrum is expanded. With reference to FIG. 7, to assure equal tension inall the cords of a radial carcass when the drum is expanded to thediameter of FIG. 6D, each of the bead gripping members or fingers 59 ismitered at each end of the portion thereof forming the materialsupporting surface 74 in mating relation to the next adjacent fingers59. 'More particularly, each end of each of these portions of thefingers 59 extends at an acute angle relative to the longitudinal axisof the drum and parallel to the next adjacent end of the next adjacentcorresponding portion of the next adjacent finger. The angle at whichthe ends of these portions of the fingers extend relative to the drumaxis is determined by the gap between these end portions when thefingers are in their radially retracted position of FIG. 1, and thedistance that the fingers are moved radially outwardly to theiroutermost position. The angle is selected so that with the fingers intheir outermost positions, and with the tire cords extending over thefingers and parallel to the axis of the drum, as indicated at C in FIG.7, each cord in the area of the gap between the fingers will besupported by a portion of a finger 59. Thus, the mating mitered ends ofeach next adjacent pair of fingers are in overlapping relationship inboth the innermost and outermost diameter of said bead gripping means.

While the material 95 remains clampingly engaged with the beads, theturn-up bladders 80 are then inflated and rolled over the beads to makethe ply turn-up and tie-in of the wire beads 96 (FIGS. 6E-6F). Duringthe ply turn-up operation the nose of each bladder is trapped in thegrooves 75 of the fingers 59 resulting in a tight turn-up around thebeads. The bladders 80 are then deflated, and the center bladder orsleeve 55 is infiated and the drum is axially contracted to preform thecarcass plies 95 to a generally toroidal shape for receiving a tread 98(FIG. 6H). Sidewalls 100 are placed on the turn-up bladders 80 and movedinto position on the carcass plies 95 (FIGS. 6H- 6I). The bladders 80and center bladder or sleeve 55 are then deflated and the cams 36returned to their rest position permitting radial retraction of thesegments 48 and fingers 59 by the rubber O-rings 52 and 65 to their restpositions close to the longitudinal axis of the building drum 10,thereby permitting removal of the finished uncured tire carcass forplacing in a mold suitable for curing r vulcanizing the carcass.

Thus, there has been provided an improved tire building machineincorporating mechanisms for clamping the beads and maintaining them inconcentric relation to the longitudinal axis of the drum and inpositions equally spaced :from the centerplane of the Ibuilding drumduring substantially the entirety of the building operation, such thatother components of the time can be more accurately applied to thecarcass plies.

While certain representative embodiments and details have been shown forthe purpose of illustrating the invention, it will be apparent to thoseskilled in the art that various changes and modifications may be madetherein without departing from the spirit or scope of the invention.

What is claimed is:

1. A tire ybuilding machine comprising a drum of generally cylindricalconfiguration and including means at each end for effecting radialexpansion of the end portions of the drum from a first diameter to asecond larger diameter, bead gripping means disposed axially outwardlyof and closely adjacent each end of the drum, each bead gripping meansbeing expandable radially of the drum between a first diameter notsubstantially greater than said first diameter of the said end portionsand a second larger diameter substantially less than said seconddiameter of said end portions, means for expanding each of said beadgripping means to said second diameter thereof, and means for expandingeach of said end portions to said second diameter subsequent toexpansion of said bead gripping means to said second diameter thereof.

2. A tire building machine as claimed in claim 1, wherein said drumfurther comprises means for moving said end portions and the beadgripping means axially 8 inwardly of the drum simultaneously with theexpansion of said end portions.

3. A tire building machine as claimed in claim 1, in which each saidbead gripping means has at its radially outermost extremity aparti-cylindrical surface registerable with a tire bead for supportingthe same in concentric relationship to the drum.

4. A tire building machine as claimed in claim 1, wherein said drumfurther comprises a center portion disposed Ibetween said end portionsand with said end portions forming a generally cylindrical rigid surfacewhen said end portions are at said first diameter thereof, means forradially expanding said center portion simultaneously with the radialexpansion of said end portions, said center portion with said endportions forming a generally cylindrical rigid surface when said endportions are at said second diameter thereof.

5. A tire building machine as claimed in claim 2, wherein said drumfurther comprises an elastomeric sleeve disposed coaxially over said endand center portions of the drum, the ends of the sleeve being fixedradially relative to the axis of the drum, and means for inflating saidsleeve simultaneously with movement of the end portions of the drumtoward each other.

6. A tire building machine as claimed in claim 4, wherein said drumfurther comprises an elastomeric sleeve disposed coaxially over said endand center portions of the drum, the ends of the sleeve being fixedradially relative to the axis of the drum, means for moving said endportions of the drum and the bead gripping means axially inwardly or thedrum simultaneously with the expansion of said end portions, and meansfor infiating said sleeve simultaneously with movement of the endportions of the drum toward each other.

7. A tire building machine as claimed in claim 5, further comprising apair of auxiliary drums disposed respectively at the oupposite ends ofsaid drum, and an infiatable turn-up bladder supported on each of saidauxiliary drums.

8. A tire building machine as claimed in claim 6, further comprising apair of auxiliary drums disposed respectively at the opposite ends ofsaid drum, and an inflatable turn-up bladder supported on each of saidauxiliary drums.

9. A tire building machine as claimed in claim 2, in which each -beadgripping means comprises a plurality of rigid members circularlyarranged concentrically of the next adjacent end portion of the drum,each of said members being mounted for movement radially of the drumaxis, said means for expanding each bead gripping means comprising cammeans movable coaxially of the drum and operatively associated with saidrigid members.

10. A tire building machine as claimed in claim 9, iu which each nextadjacent pair of said rigid members have next adjacent ends extending atacute angles to the longitundinal axis of the drum, whereby said endsare in overlaping relationship in both said first and second diametersof said bead gripping means.

11. A tire building machine as claimed in claim 9, wherein said drumfurther comprises means forming an annular chamber extending coaxiallyof the drum axis and disposed adjacent each end of the drum, and anannular piston disposed in each chamber, said cam means being mountedfor movement with said piston.

12. A tire building machine as claimed in claim 11, wherein each cammeans comprises a conical surface inclined outwardly of the drum axisand at its outer end terminating in a cylindrical surface disposedcoaxially of the drum axis, said conical surface being operative to movethe associated rigid members radially outwardly of the drum axis andsaid cylindrical surface being operative to lock said associated rigidmembers in their radially outermost position.

13. A tire building machine as claimed in claim 9, further comprising apair of auxiliary drums disposed respectively adjacent the end portionsof the drum and mounted for movement axially of the drum with said endportions and bead gripping means, an inflatable turnup bladder supportedon each of said auxiliary drums and in its uninflated condition beinggenerally cylindrical and disposed coaxially of the drum axis, one endof each bladder being disposed next adjacent the respectively associatedbead gripping means, each of said rigid members of said bead -grippingmeans being provided with an arcuate groove extending about the drumaxis and receiving the next adjacent end portion of the respectivelyassociated bladder.

14. A tire building machine as claimed in `claim 12, wherein each ofsaid rigid members is provided at its radially outermost extremity witha parti-cylindrical surface having its axis extending parallel to theaxis of the drum.

15. A tire building machine as claimed in claim 1, wherein each meansfor effecting expansion of an end portion of the drum comprises aplurality of segments circularly arranged concentrically of the drumaxis and each having at its radially outermost extremity a rigidgenerally parti-cylindrical surface, a plurality of lifter membersrespectively associated with and mounted for movement with saidsegments, said lifter members extending radially inwardly of the drumaxis, and means for guiding said lifter members for movement radially ofthe drum axls.

16. A tire building machine as claimed in claim 15, further comprisingcam means operatively associated with the lifter members.y

17. A tire Ibuilding machine as claimed in `claim 16, wherein said drumfurther comprises means at each end thereof forming an annular chamberdisposed coaxially of the drum axis, an annular piston disposed in saidchamber, said cam means being mounted for movement with said piston.

18. A tire building machine as claimed in claim 17, wherein said cammeans comprises a conical surface arranged concentrically of the drumaxis and terminating in its outer end in a cylindrical surface operativeto lock said lifter members and segments in their radially outermostpositions.

19. A tire building machine as claimed in claim 1, wherein said meansfor effecting expansion of each end portion of the drum comprises aplurality of radially movable members, each bead gripping meanscomprising a plurality of radially movable members, the means foreffecting expansion of each of said end portions of the drum and themeans for expanding the bead gripping means next adjacent each of saidend portions comprising common cam meas movable coaxially of the drum,means operatively connecting said radial movable members of the beadgripping means with the cam means when the bead gripping means are insaid first diameter thereof, means for operatively connecting said cammeans and said radially movable members for expanding the end portion ofthe drum, and means to move said cam means to effect sequential movementof said bead gripping means and end portions to said second diametersthereof.

20. A tire building machine as claimed in claim 19, wherein saidradially movable end portions of the drum are offset `about the drumaxis with respect to the radially movable member of said bead grippingmeans.

21. A tire building machine as claimed in claim 19, wherein said drumfurther comprises means mounting the radially movable members foreffecting expansion of each end portion of the drum and said radiallymovable members of the next adjacent bead gripping means and theassociated cam means for movement together axially of the drum.

22. A tire building machine as claimed in claim 21, wherein said drumfurther comprises means adjacent each 10 end thereof providing anannular chamber extending coaxially of the drum, and an annular pistonreceived in said chamber, said cam means being mounted for movement withsaid piston.

23. A tire building machine as claimed in claim 22, wherein said commoncam means includes a conical surface disposed coaxially of the drum andterminating at the radially outer end thereof in one end of acylindrical surface disposed coaxially of the drum and which at itsother end terminates at one end of a second conical surface disposedcoaxially of the drum, said second conical surface being inclinedradially outwardly of the drum axis from said one end thereof andterminating at its other end at one end of a second cylindrical surfacedisposed coaxially of the drum.

24. A tire building machine as claimed in claim 23, wherein said meansoperatively connecting the radially movable members of each beadgripping means with said cam means comprises a plurality of leversrespectively associated with the last mentioned radially movablemembers, each of said last mentioned members being pivoted at one endfor movement about an axis fixed radially relative to the axis of thedrum, the other end of each lever carrying a roller engageable with saidcam means, and a second roller mounted intermediate the ends of eachlever and engageable with the respectively associated radially movablemember of said bead gripping means.

25. A tire building machine as claimed in claim 1S, wherein said meansfor guiding said lifter members at each end of the drum comprises amember extending about the drum axis and movable longitudinally of thedrum axis, said bead gripping means at each end of the drum comprising aplurality of fingers circularly arranged concentrically of the drumaxis, and means on the last mentioned member slidably supporting saidfingers for movement radially of the drum axis.

26. A tire building machine as claimed in claim 1S, wherein said meansfor guiding said lifter members comprises a housing disposed coaxiallyof the drum, means for moving said lifter members radially outwardly ofthe drum axis, an elastomeric sleeve disposed over said segments, meansfixing each end of the sleeve relative to the next adjacent housingcomprising a clamping ring disposed axially outwardly of the drumrelative to the housing, said bead gripping means at each end of thedrum comprising a plurality of fingers circularly arranged con--centrically of the drum axis, means on the clamping ring slidablyreceiving said plurality of fingers and guiding the same for movementradially of the drum axis, and means for moving the housings and beadgripping means axially inwardly of the drum simultaneously with themovement of said lifter members radially outwardly of the drum axis.

27. A tire building machine as claimed in claim 26, wherein each of saidfingers at its radially outermost extremity is provided with a rigidparti-cylindrical surface registerable with a tire bead for supportingthe same in concentric relationship to the drum.

28. A tire |building machine as claimed in claim 27, in which theparti-cylindrical surfaces of said segments are offset angularly aboutthe drum axis with respect to the parti-cylindrical surfaces of saidfingers.

29. A tire building machine as claimed in claim 26, wherein said drumfurther comprises a rotatable shaft extending coaxially of the drum, ahub slidably mounted on the shaft adjacent each end of the drum formovement longitudinally of the shaft, each hub being connected to one ofsaid housings for movement therewith, means providing each hub with anannular chamber disposed coaxially of the drum axis, an annular pistondisposed in each chamber, and means for connecting said annular pistonto said lifter members in said housing and to said fingers respectivelyassociated therewith for effecting sequential movement of said fingersand lifter members radi- 1 1 ally outwardly of the drum in response tomovement of said annular piston longitudinally of the drum axis.

30. A tire building machine including a drum comprising a plurality ofcircularly arranged bead gripping members disposed concentrically of thedrum axis at each end of the drum, said bead gripping members beingmovable radially of the drum axis, a generally -annular inflatablebladder disposed coaxially of the drum and axially outwardly of the drumwith respect to the bead gripping members, the bladder being anchoredrelative to the drum axis adjacent the bead gripping members and havinga nose portion extending toward the bead gripping members, and means onthe bead gripping members receiving the nose portion of the bladder whenthe bladder is deilated and trapping said nose portion during inflationof the bladder.

31. A tire building machine as claimed in claim 30, wherein each of saidbead gripping members is provided with a parti-cylindrical surfaceextending about the drum axis, said means for receiving the nose portionof the bladder comprising an arcuate groove in each bead gripping memberdisposed radially inwardly of and in registry with saidparti-cylindrical surface.

32. A tire building machine including a drum comprising a plurality ofcircularly arranged bead gripping members disposed concentrically of thedrum at each of the opposite ends thereof, each bead gripping memberhaving at its radially outermost extremity a parti-cylindrical surfaceregisterable with a tire bead for supporting the same in concentricrelationship to the drum, means mounting said bead gripping members formovement radially of the drum axis from a rst diameter substantiallyequal to the diameter of the drum to a second larger bead grippingdiameter, and means for moving said bead gripping members simultaneouslyradially outwardly of the drum axis comprising cam means.

33. A tire building machine as claimed in claim 32, in which each nextadjacent pair of bead gripping members have next adjacent end portionsextending at acute angles to the longitudinal axis of the drum, wherebysaid end portions are in overlapping relationship in both said lirst andsecond diameters of said bead gripping members.

34. A tire building machine as claimed in claim 32, wherein said cammeans comprises, in association with the bead gripping members at eachend of the drum, a conical surface arranged coaxially of the drum axis,.and means mounting said cam means for movement longitudinally of thedrum axis.

35. A tire building machine as claimed in claim 34, in which said meansmounting said cam means comprises means forming an annular cylinderdisposed coaxially of the drum, and an annular piston slidably receivedin said cylinder, said cam means being mounted for movement with saidpiston.

36. A tire building machine as claimed in claim 35, further comprisingadjacent each end of the drum an end member mounted for movement withsaid means forming said cylinder in a direction longitudinally of thedrum axis, means on said end member for guiding said bead engageablemembers for movement radially of the drum axis.

37. A tire building machine as claimed in claim 36, further comprising alink respectively associated with each of said bead griping means, oneend of the link being pivoted on the next adjacent end member for movinggenerally radially of the drum axis, means on the other end of said linkcooperably engageable with said conical member, and means intermediatethe ends of said link er1- gageable with the respectively associatedbead gripping member for movement of the bead gripping member radiallyoutwardly of the drum axis in response to movement of said piston in adirection longitudinally of the drum axis.

38. A tire building machine including a drum comprising a pair of endmembers disposed at opposite ends respectively of the drum, a pluralityof circularly arranged lifter rods disposed concentrically of each endof the drum and slidably supported by the next adjacent end member formovement radially of the drum axis, each lifter rod carrying at itsouter end a segment having a parti-cylindrical outer surface, a hub ateach end of the drum provided with an annular cylinder disposedconcentrically of the drum axis, an annular piston received in saidcylinder, a conical cam disposed coaxially of the drum and mounted formovement with each piston, cam follower means on each lifter rodengageable with such cam to elfect radially outward movement of therespectively associated segments in response to movement of said pistonlongitudinally of the drum, and means connecting each end member withthe next adjacent hub for movement of the two simultaneously andlongitudinally of the drum axis.

39. A tire building machine including a drum comprising at each endthereof a plurality of circularly arranged rigid segments circularlyaranged concentrically of the drum axis, means mounting said segmentsfor movement radially of the drum axis, the segments at one end of thedrum being spaced apart axially of the drum from the segments at theother end thereof, a plurality of substantially rigid parti-cylindricalcover plates disposed between the segments at each end of the drum, saidcover plates being circularly arranged concentrically of the drum axis,the ends of said cover plates being in overlying engagement with therespectively next adjacent ends of the segments and means for movingsaid cover plates radially of the drum axis simultaneously with themovement of said segments whereby said drum provides a rigid cylindricalmaterial supporting surface over the entire length thereof in said firstdiameter and said second diameter of said segments.

40. A tire building machine as claimed in claim 39, further comprisingmeans for moving the segments at each end of the drum toward and awayfrom the segments at the other end of the drum, said cover plates beingslidably engaged with said segments whereby said segments telescopewithin said cover plates during movement axially inwardly of the drum.

41. A tire building machine as claimed in claim 40, further comprisingan elastomeric sleeve disposed about said segments and cover plates, theends of said sleeves being anchored relative to said segments, and meansfor iniiating said sleeve during movement of said segments axiallyinwardly of the drum.

42. A tire building machine including an expandable tire building drum,said drum comprising at each end thereof a set of circularly arrangedsegments disposed concentrically of the drum axis, each segmentincluding a rigid parti-cylindrical material supporting surface facingradially outwardly of the drum, means for moving said segments radiallyof the drum axis from a first diameter to a second larger diameterwherein said segments are spaced apart in a direction circumferentiallyabout the drum axis, a set of bead gripping members respectivelyassociated with each set of segments, each set of bead gripping memberscomprising a plurality of the same circularly arranged and disposedconcentrically of the drum axis, said bead gripping members beingdis-posed axially outwardly of the drum with respect to the respectivelyassociated set of segments, each bead gripping member comprising aparti-cylindrical rigid surface extending about the drum axis, said beadgripping members being mounted for movement radially of the drum axisbetween a iirst diameter and a second larger diameter wherein said beadgripping members are spaced apart in a direction circumferentially aboutthe drum axis, the bead gripping members being disposed about the drumaxis with respect to the respectively associated set of segments toprovide that when the segments are in said second diameter thereof thespace between next adjacent segments is wholly in registry with aparti-cylindrical 13 surface on a next adjacent one of said beadgripping members.

43. A tire building machine as claimed in claim 42, in which saidparti-cylindrical surface of each bead gripping member is disposed atthe radially outermost extremity thereof, the portions of each nextadjacent pair of bead gripping members forming said parti-cylindricalsurfaces thereof having next adjacent end portions extending at acuteangles to the longitudinal axis of the drum, which said end portions arein overlapping relationship in iboth said rst and second dia-meters ofsaid bead gripping members.

References Cited UNITED STATES PATENTS 2,614,952 10/1952 Kraft 156-4023,035,629 5/1962 Vanzo et al. 156-403 14 Vanzo et al. 156-132 X Vanzo'et al. 156-401 X Giletta et al 156--132 Allitt 156-398 X Nebout 156-401X Ndler et al. 156-401 Ndler 156-401 Kehoe et al. 15G-401 X Pizzo156-398 U.S. C1. XR.

